Sample and population score matrices and sample correlation matrices from an arbitrary population correlation matrix

A method for generating sample and population score matrices and sample correlation matrices from a given population correlation matrix is developed. An example giving the desired matrices for a population Guttman simplex correlation matrix is presented.The computations for this paper were done on Illiac, an electronic computer of the Digital Computer Laboratory of the University of Illinois. Mr. S. Hunka assisted in these computations. The final version of this paper was prepared while the senior author was a U. S. Public Health Service Fellow at the Center for Advanced Study in the Behavioral Sciences.     

Right Hemisphere Activation during Indirect Semantic Priming: Evidence from Event-Related Potentials

Healthy subjects performed a lexical decision task in a semantic priming paradigm while event-related potentials (ERPs) were recorded from 64 channels. Semantic distance between prime and target was varied by including directly, indirectly, and nonrelated word pairs. At centro-parietal electrodes an N400 to nonrelated pairs was elicited bilaterally which was sensitive only to direct, but not to indirect semantic priming. These N400 priming effects were mirrored by the RT data. At inferior fronto-temporal sites directly related words showed ERP priming effects over both hemispheres. However, indirectly related words only elicited ERP priming effects over the right hemisphere. These results support the hypothesis that the right hemisphere semantic system is involved in processing of remote semantic information.     

A SELF-MONITORING PACKAGE FOR TEACHING SUBTRACTION WITH REGROUPING TO STUDENTS WITH LEARNING DISABILITIES

In this investigation, we evaluated the effectiveness of a self-monitoring package with 3 learning disabled students whose responding to subtraction problems had been highly inconsistent and unsuccessful. Following a two-phase baseline of didactic instruction and special incentives, an error analysis was used to develop individualized self-monitoring checklists that the students then responded to as they completed their subtraction assignments. In the context of a multiple baseline design, the self-monitoring procedures produced immediate gains in correct responding, with more stable levels of successful performance occurring across sessions. In a subsequent maintenance phase, the checklists were removed and the previous incentives condition was reinstated, resulting in continued levels of successful responding. The results are compared to the literature on self-monitoring and learning disabilities and discussed in terms of the continuing need for effective and efficient instructional strategies.     

When Thinking About Work Makes Employees Reach for Their Devices: A Longitudinal Autoregressive Diary Study

Based on the stressor-detachment model, previous research has assumed that work-related ICT use in the evening impairs psychological detachment. However, since most of the studies to date have assessed cross-sectional relationships, little is known about the actual direction of effects. In this 5-day diary study, we implemented a day-level longitudinal model to shed light on the causal relationships between work-related ICT use, detachment, and task progress (N?=?340 employees, N?=?1289 day-level cases). We also investigated the role of unfinished work tasks because we assumed, based on boundary theory, that they are a driving force leading to impaired detachment and work-related ICT use in the evening. Contrary to current research consensus but in line with our expectations, we found that low psychological detachment increased work-related ICT use and task progress. We found no evidence for reversed lagged effects. These results applied both to planned and unplanned ICT use. Furthermore, our results support the notion that unfinished work tasks precede ICT use and detachment. Thus, our findings suggest that work-related ICT use should not be treated as a stressor in its own right in the stressor-detachment model. Instead, it needs to be investigated as a behavioral outcome that employees engage in when they cannot detach from work.

     

Using a Response Time–Based Expected A Posteriori Estimator to Control for Differential Speededness in Computerized Adaptive Test

This study investigates using response times (RTs) with item responses in a computerized adaptive test (CAT) setting to enhance item selection and ability estimation and control for differential speededness. Using van der Linden’s hierarchical framework, an extended procedure for joint estimation of ability and speed parameters for use in CAT is developed following van der Linden; this is called the joint expected a posteriori estimator (J-EAP). It is shown that the J-EAP estimate of ability and speededness outperforms the standard maximum likelihood estimator (MLE) of ability and speededness in terms of correlation, root mean square error, and bias. It is further shown that under the maximum information per time unit item selection method (MICT)—a method which uses estimates for ability and speededness directly—using the J-EAP further reduces average examinee time spent and variability in test times between examinees above the resulting gains of this selection algorithm with the MLE while maintaining estimation efficiency. Simulated test results are further corroborated with test parameters derived from a real data example.     

Educators' Perceptions of Attention Deficit Hyperactivity Disorder: An Exploratory Study

The study investigated the perceptions of educators about Attention Deficit Hyperactivity Disorder, specifically their views on its incidence, causes and appropriate interventions in school settings. Five purposively selected educators from a private school participated in the study. Ethnographic interview was used to collect and analyze the data. The results revealed that the educators considered ADHD mainly a physiological disorder with primarily genetic and environmental causes. Regardless the educators preferred medication as the intervention method despite being aware of additional intervention methods.     

An Analysis of the Status and Stability of the Behaviors of Students with Emotional and Behavioral Difficulties

Students with emotional and behavioral problems are placed in a variety of classroom settings, presumably where their needs can be best served. Little attention, however, has been dedicated to monitoring their behavioral progress in these settings. This study analyzed data on student engagement, disruption, and destruction during 10 types of instructional activities. Data were collected at two times across one academic year in Pennsylvania and California in 90 classrooms, ranging from grades 1 to 12. Tests of mean comparisons (i.e., independent samples and paired t-tests) and the association between variables (i.e., bivariate correlation analysis) were conducted to address a number of concerns regarding the status and stability of classrooms for students with EBD. Independent paired sample t-tests showed a lack of significant improvement in behaviors across time, and the correlational data reflect a significant relationship between student engagement and classroom activity. Findings are discussed in light of limitations and directions for future research. In addition, practical implications are noted.     

A Comparison of Quality of Life Variables for Students with Emotional and Behavioral Disorders and Students Without Disabilities

The importance of quality of life has been increasingly recognized in the field of special education. To date, however, there are no studies focusing exclusively on students with emotional and behavioral disorders (EBD). This study examined quality of life differences between students with EBD and their nondisabled peers in four domains: (a) General quality of life; (b) Self; (c) Relationships; and (d) Environment. Additional analyses compared parent and adolescent ratings. Results indicated adolescents with EBD were significantly more dissatisfied with their quality of life in all domains than their non-EBD peers. No significant within group differences were found for gender or age; however, EBD students in self-contained schools rated self and environment significantly higher than their peers with EBD in public schools. Parents of adolescent with EBD rated their adolescent’s quality of life significantly lower than their adolescent did, while parents of non-EBD adolescents rated their adolescent’s quality of life as significantly higher than did their adolescents. This study has several implications for programming to improve the outcomes among this group of students.     

Bifactor and item response theory analyses of interviewer report scales of cognitive impairment in schizophrenia

A psychometric analysis of 2 interview-based measures of cognitive deficits was conducted: the 21-item Clinical Global Impression of Cognition in Schizophrenia (CGI-CogS; Ventura et al., 2008), and the 20-item Schizophrenia Cognition Rating Scale (SCoRS; Keefe et al., 2006), which were administered on 2 occasions to a sample of people with schizophrenia. Traditional psychometrics, bifactor analysis, and item response theory methods were used to explore item functioning and dimensionality and to compare instruments. Despite containing similar item content, responses to the CGI-CogS demonstrated superior psychometric properties (e.g., higher item intercorrelations, better spread of ratings across response categories) relative to the SCoRS. The authors argue that these differences arise mainly from the differential use of prompts and how the items are phrased and scored. Bifactor analysis demonstrated that although both measures capture a broad range of cognitive functioning (e.g., working memory, social cognition), the common variance on each is overwhelmingly explained by a single general factor. Item response theory analyses of the combined pool of 41 items showed that measurement precision is peaked in the mild to moderate range of cognitive impairment. Finally, simulated adaptive testing revealed that only about 10 to 12 items are necessary to achieve latent trait level estimates with reasonably small standard errors for most individuals. This suggests that these interview-based measures of cognitive deficits could be shortened without loss of measurement precision.